V_ARRAY.ZIP Contains the following files: VIR.H 2351 - Header file for virtual array functions VIR.OBJ 4911 - Object file containing virtual array functions PRIMES.C 2325 - Prime number generator source code PRIMES.EXE 65392 - Prime number generator program README.TXT 4079 - This text file The program PRIMES is a demonstration using a virtual array. To run the program, simply type PRIMES at the DOS prompt. You will find that the prime number generator quickly generates a large volume of primes. To stop the pro- gram, simply press a key (I suggest ). Whatever key you hit will be passed on as if it was typed at the DOS prompt. PRIMES produces a file containing each prime number it generates. The prime numbers are stored as an array of long integers. PRIMES is capable of producing a list of all prime numbers less than 2,000,000,000 if you have the file space for it. Since such a large volume of prime numbers would take some time to compile, PRIMES has been designed to pick up where it left off when it is restarted. The file containing the prime numbers is named PRIMES.DAT. The virtual array functions in VIR.* are designed to allow access to an arbitrarily large array. Any type of data or structure can be accessed with these functions. Array access is straight forward, allowing your code to be simple and uncluttered. All disk caching / swapping is done automatically by VIR. VIR doubles as a buffered file access method. Since the arrays that VIR produces become disk files, any disk file can be accessed as an array of elements. (For instance, characters, data records,..) VIR has provisions for file sharing such as locking and unlocking groups of elements or denying access to files. In fact, VIR was developed as the primary file access method for a multi-user relational data base. When initializing a virtual array, you are required to specify the buffering characteristics. By altering these, you can achieve significant improvements in overall program performance as well as insuring automatic transaction reversal (Requires TTS) in the event of a program crash. Since VIR takes care of all these nasty details, your application can get on with nifty algorythms such as shown in this demo. In fact, with an extra macro or two, you can access a virtual array almost the same as if it were a simple array. BUT ENOUGH EXPLAINING.... The purpose of this demo is to bring in a couple dollars and give out a nifty little bit of code. Feel free to use these functions in any of your pro- grams. (if you can figure it all out.) It was compiled using the SMALL memory model under TURBO C V2.0. I wish to ecnourage you to evaluate them. GOOD LUCK! If you come up with anything really nifty using this limited version, it would be nice to see my name mentioned in your source credits. I would also like to see a copy of the program and any comments you might have on how to improve the functions. Feel free also to pass this demo on to anyone you think might have a use for it.... especially other BBS's! However, all of these files must remain intact and complete! If you really want to be able to use these functions, simply send $10.00 to me: Peter G. McNeil c/o Persnickety Inc. 22446 Davis Drive #187 Sterling, Va. 22170 PHONES:----------- DAY (703) 450-6727 EVE (301) 725-3239 FAX (703) 450-5574 FOR THIS YOU GET!!! - Complete source code for the VIR fucntions. - An explanation of each function and it's use. - A discussion of the caching/swaping algorythm. - A discussion of mult-user file access methods using VIR. PLEASE SPECIFY 3.5" or 5.25" disk. If you are a teacher and you want to use this in your class, I would be so tickled that I would send it to you for free! Just send me a letter on official letter head and it will be on it's way. This code represents a lot of thought, develpment, testing, and frustration. I hope it comes to some good use for you. It has proven very useful to me. Thanks!!